1. Technical Field
The present invention relates to a semiconductor circuit device, an oscillator, an electronic apparatus, and a moving object.
2. Related Art
In an AT cut quartz crystal resonator constituting a temperature compensated crystal oscillator (TCXO), a frequency fluctuates while drawing a curve approximated to a cubic curve which has an inflection point around 25° C. due to a change in ambient temperature. An oscillation circuit and the like constituting the oscillator also have temperature characteristics, and thus a frequency fluctuates due to influences thereof. In the TCXO, a voltage signal for compensating for the frequency fluctuation is generated by a temperature compensation circuit and is applied to a varicap diode provided in the oscillation circuit. Therefore, the frequency fluctuation due to the change in ambient temperature is minimized, and thus high frequency accuracy is realized.
As an example of such a TCXO, JP-A-2007-67967 discloses a TCXO using a semiconductor substrate provided with an oscillation circuit, an output buffer circuit, and a temperature sensor circuit, in which the output buffer circuit and the temperature sensor circuit are disposed in diagonal corners or the same side corners of the semiconductor substrate.
In JP-A-2007-67967, if the output buffer circuit which is one of heat generation sources is close to the temperature sensor circuit, a temperature of the output buffer circuit is easily transferred to the temperature sensor circuit, and thus a temperature detected by the temperature sensor circuit is higher than temperatures of regions other than the output buffer circuit. As a result, there is a possibility that a temperature may not be accurately detected. For this reason, for example, in a case where temperature compensation is performed on the basis of an output signal from the temperature sensor circuit when the TCXO is activated, an influence of a temperature in the vicinity of the output buffer circuit may be strongly received, and thus an output frequency may fluctuate.